1. Technical Field
Embodiments of the present disclosure relate generally to integrated circuits (IC), and more specifically to controlling the slew-rate of an output buffer.
2. Related Art
An output buffer is generally a circuit that receives an input signal (often in digital form), and provides a corresponding output signal with increased drive (lower output impedance, and therefore ability to drive larger values of loads). Typically, in an IC, the output signal is provided on a pad/pin of the IC. For example, data signals generated internally within a processor unit (e.g., central processing unit), are typically provided in buffered form to external components via corresponding output buffers.
Slew rate of an output buffer is the rate of change with respect to time of the output signal provided by the buffer, and may depend on the value of load connected to the output. With respect to an output buffer that operates on digital signals, slew rate generally refers to the rise and/or fall times of the output signal. The rise (or fall) time may be measured between specified voltage values of the signals, for example, from 10% to 90% of the maximum (or minimum) value, or from 30% to 70% of the maximum (or minimum) value, etc.
The slew rate of an output buffer may be required to be controlled while meeting the specific requirements and/or provide features that can take advantage of the corresponding environment.